The present invention is concerned with a method and apparatus for stabilizing a vehicle which is lifted off the ground for service.
When certain work needs to be done on a vehicle such as changing the shock absorbers or the springs, it is a common practice to use a hydraulic lift to raise the automobile to above head height of the mechanic. A widely used jack or lift is one that has a large central hydraulicly operated shaft which is extendable from the floor level to a height of 8 or 10 feet or more. Adjustable arms are pivotally attached to the hydraulic lift so that after a car has been driven over the hydraulic shaft, then the arms can be extended outwardly so that they will be under the frame. Then the hydraulic means is actuated and the car is lifted to the desired height.
When this occurs, it is apparent that the wheels are not directly supported by the hydraulic shaft or the arms but are supported by the suspension system. The tires are hanging down from their normal position in relation to the upper portion of the car and is held there only by the suspension system which is under tension and not in compression which is normal. For service such as changing shocks, the operation may, in some instances, become dangerous. For example, when you take the rear shock loose, the rear end of the car, that is the wheel and shaft can drop up to three or four inches. This can cause an unbalance unstabilizing the car and there have been instances where the car has fallen from the rack, demolishing the car and endangering human lives. When changing a front coil spring after taking the ball joint loose, the spring can literally fly in an undetermined direction. This is, of course, very dangerous.